title: Long-term treatment of anxiety disorders with pregabalin: a 1 year open-label study of safety and tolerability.
abstract: OBJECTIVE
  Short-term clinical trials have demonstrated the efficacy and safety of pregabalin in the treatment of generalized anxiety disorder (GAD). This study examined long-term safety and tolerability of pregabalin in patients with GAD, social anxiety disorder (SAD), or panic disorder (PD).
  
  
  METHODS
  Patients (n = 528) completing one of four randomized, double-blind, placebo-controlled trials of pregabalin for GAD, SAD, or PD were treated, open label, with flexible-dose pregabalin (150-600 mg/day) for 1 year.
  
  
  BACKGROUND
  NCT00150449.
  
  
  METHODS
  The primary outcomes were safety and tolerability. Illness severity was assessed at baseline and Weeks 27/52 using the Clinical Global Impression of Severity (CGI-S) scale. Patients were characterized as 'responders' or 'non-responders' based on CGI-S scores ≤2 and >2, respectively. Analyses were performed on the total anxiety (GAD, SAD and PD) and GAD groups.
  
  
  RESULTS
  During 1 year of treatment with pregabalin, dizziness (12.5%) was the only treatment-related adverse event (AE) occurring ≥10%. Somnolence, weight gain, headache and insomnia occurred at 7.6%, 5.5%, 5.3% and 4.7%, respectively. Few treatment-related AEs were rated as severe in the total anxiety (5.1%) or GAD (3.6%) groups. Discontinuation rates due to AEs were similar (9.7% and 10.6%, respectively). No clinically significant laboratory, electrocardiogram, or other treatment-related safety findings were noted, except for treatment-related weight gain, which occurred in both the total (24.4%) and GAD (19.4%) groups. Mean CGI-S scores were similar at baseline in the total (n = 528; score, 3.4) and GAD groups (n = 330; score, 3.6), and CGI-S responder rates were similar at last-observation-carried-forward endpoint (51.3% and 48.1%, respectively).
  
  
  CONCLUSIONS
  Pregabalin was generally well tolerated in the long-term treatment of anxiety disorders. Improvement in illness severity was maintained over time. The key limitations of this study were that it was not randomized and neither placebo- nor active-comparator-controlled.
authors.affiliation: Imperial College School of Medicine, University of London , London , UK.
authors.forename: Stuart
authors.initials: S
authors.lastname: Montgomery
authors.forename: Birol
authors.initials: B
authors.lastname: Emir
authors.forename: Hannah
authors.initials: H
authors.lastname: Haswell
authors.forename: Rita
authors.initials: R
authors.lastname: Prieto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001008:Anxiety Disorders / Q000188:drug therapy* / Q000503:physiopathology; D002121:Calcium Channel Blockers / Q000008:administration & dosage* / Q000009:adverse effects; D004311:Double-Blind Method; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000069583:Pregabalin; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*
chemical_list: D002121:Calcium Channel Blockers; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid